Some aspects of avian frugivory in a north temperate area relevant to tropical forest

Abstract

We discuss aspects of frugivore behavior which are important in English woodland but which either seem to contrast with what is found in tropical forest or suggest the need for further research in tropical forest. (1) Impact of predators. In our study area this is a main factor promoting social feeding behavior, affecting the choice of fruiting plant and part of the plant exploited, and determining the feeding routine (in comparison with which, searching/handling time is relatively unimportant). Little evidence on these points exists for tropical forest. (2) Defense of fruit. Long-term defense of fruit resources is important for at least one English frugivore. So far only a few instances of short-term defense are known from the tropics, but long-term defense is likely in some circumstances and may affect patterns of seed dispersal. It is suggested that mistletoes are the most likely plants for long-term fruit defense. (3) Seed predators. Tropical data suggest that avian seed predation is unimportant for most fleshy bird-dispersed fruits, in marked contrast to temperate woodland, where avian seedpredators may destroy a large proportion of a fruit crop. It is suggested that the seed defenses of tropical forest plants are more effective than those of north temperate plants.